1 Create a block using two different colours as above, cut 3cm wide strips of a darker fabric and use these to make an overlapped border all around. Cut 28, 6.5cm squares of coloured fabric, sew two sets of six squares together in a line and stitch these to the top and bottom edges of the block.

2 Sew the remaining squares into two sets of eight and stitch these down either side, carefully matching the seams at the corners, then press the panel. Pin the panel, face up, onto a 46cm square of heavyweight cotton or blackout material and topstitch along the seam lines, cut a second square of heavyweight fabric and stitch to the panel, right sides together, along three sides.

3 Cut 4.5cm wide strips of fabric and join end to end to make a piece 97cm long, fold in the short ends by 5mm and hem, place the strip along the top edge, right side against the inside of the bag and stitch in place, making sure the hemmed ends meet at one side.